Secure Communications in Tiered 5G Wireless Networks With Cooperative Jamming
Secure Communications in Tiered 5G Wireless Networks With Cooperative Jamming
复制标题
DOI：
10.1109/twc.2019.2912611
复制
发表时间：
2019-06-01
影响因子：
10.4
通讯作者：
Chen, Dechang
中科院分区：
文献类型：
--
作者：
Huo, Yan;Fan, Xin;Chen, Dechang
协作干扰被认为是一种在存在窃听者的情况下保护无线传输的一种很有前途的物理层方法。研究了两层5G异构网(HetNet)中的协作干扰问题，其中宏蜂窝层的宏基站(MBS)采用大规模天线阵列提供空间分集，而本地小区层的本地基站(LBS)采用非正交多址(NOMA)来容纳密集本地用户(LU)。在存在不完全信道状态信息的情况下，提出了三种适用于不同安全需求场景的稳健保密传输算法。第一种算法采用稳健的波束形成(RBA)，旨在优化宏蜂窝中的MU的保密率。第二种算法提供稳健的功率分配(RPA)，可以优化本地小区中逻辑单元的保密率。第三种算法解决了一个健壮的跨层联合优化(RJO)问题，该问题稳健地寻求目标MU和目标LU的最大保密和速率。我们使用凸优化技术来寻找这些高度非凸性问题的可行解。数值结果表明，所提出的算法在改善双层HetNet的保密性能方面是非常有效的。
Cooperative jamming is deemed as a promising physical layer-based approach to secure wireless transmissions in the presence of eavesdroppers. In this paper, we investigate cooperative jamming in a two-tier 5G heterogeneous network (HetNet), where the macrobase stations (MBSs) at the macrocell tier are equipped with large-scale antenna arrays to provide space diversity and the local base stations (LBSs) at the local cell tier adopt non-orthogonal multiple access (NOMA) to accommodate dense local users (LUs). In the presence of imperfect channel state information, we propose three robust secrecy transmission algorithms that can be applied to various scenarios with different security requirements. The first algorithm employs robust beamforming (RBA) that aims to optimize the secrecy rate of a marcouser (MU) in a macrocell. The second algorithm provides robust power allocation (RPA) that can optimize the secrecy rate of an LU in a local cell. The third algorithm tackles a robust joint optimization (RJO) problem across tiers that seek the maximum secrecy sum rate of a target MU and a target LU robustly. We employ convex optimization techniques to find feasible solutions to these highly non-convex problems. The numerical results demonstrate that the proposed algorithms are highly effective in improving the secrecy performance of a two-tier HetNet.